1. The Field of the Invention
The present invention relates to the field of dental instruments. In particular, the present invention relates to endodontic files that are used for debriding and cleaning root canals during endodontic procedures. Even more particularly, the present invention relates to flocked endodontic files that are used to remove pulp, necrotic tissue, organic debris, and other potential irritants from root canals in preparation for receiving dental filling materials.
2. The Relevant Technology
Endodontics is the branch of dentistry that generally deals with infections and diseases of dental pulp. Dental pulp, which is found in the pulp chamber and root canals of the tooth, comprises a vascular tissue that is generally composed of nerve fibers and blood vessels that nourish the tooth during its growth and development. When bacteria gains access to the pulp, either through a fractured tooth or a deep cavity, the pulp becomes infected and will die unless the body is able to repair and heal the pulp. Pulp can also become infected when the tooth suffers from trauma or a periodontal disease.
When the pulp becomes so severely infected or otherwise damaged that it cannot be healed, it is necessary to remove the pulp to relieve the pain and to prevent infection from spreading beyond the tooth. Pulp can either be removed by extracting the tooth or by performing an endodontic procedure, such as a root canal.
During a root canal procedure, the endodontist accesses the root canal and debrides the root canal of potential irritants such as necrotic tissue, pulp, bacteria, bacterial byproducts and other debris. Debridement essentially consists of loosening the potential irritants from the sides of the root canal with an endodontic tool, such as a file, and then flushing the potential irritants out of the root canal with an irrigant. Some irrigants may comprise or are used in combination with antibacterial disinfectants and/or chelators to sanitize the root canal and to dissolve remaining debris.
The final step of performing the root canal procedure, which is known as obturation, involves filling the root canal with a filling material such as gutta percha or amalgam and sealing the filling with a sealer cement to prevent future contamination of the root canal.
One problem with existing methods and devices for performing endodontic procedures, however, is that the anatomy of the tooth makes it impossible to completely clean potential irritants out of the root canal. In particular, the root canal is irregularly shaped, having contoured surfaces, recessed regions and accessory canals. The irregular shape of the root canal prevents existing endodontic files from reaching and abrading the entire surface area of the root canal, thereby leaving portions of live, diseased or necrotic pulp and debris undisturbed.
Some existing flexible endodontic files are capable of following the irregular contours of the perimeter surfaces of the root canal. However, even these existing flexible files are unable to completely reach and abrade the recessed regions and accessory canals of the root canal. Accordingly, to provide access to the hard-to-reach regions of the root canal, it is often necessary to “reshape” or file down the walls of the root canal. This however, is undesirable because it can cause overthinning of the root canal which increases the risk that an endodontic tool, such as a file or an irrigation cannula, will fracture or perforate the walls of the root canal, causing pain to the patient and further complicating the endodontic procedure.
Reshaping is sometimes required to widen narrow passages of the root canal in order to access apical regions and to minimize hydraulic pressures during obturation. However, filing down the walls of the root canal unnecessarily, simply to provide access to recessed regions for debridement is undesirable, not only because it increases the risks associated with overthinning, but also because it increases the time, and hence the cost, associated with performing the root canal. Furthermore, even after reshaping the root canal, existing endodontic files are still sometimes unable to adequately reach and abrade the recessed regions and accessory canals.
Accordingly, there is currently a need in the art for improved endodontic files for debriding root canals during endodontic procedures.